/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.optimize;

import proguard.classfile.*;
import proguard.classfile.visitor.MemberVisitor;

/**
 * This MemberVisitor delegates all its method calls to another MemberVisitor, but only for Member objects that are
 * marked as kept.
 *
 * @see KeepMarker
 *
 * @author Eric Lafortune
 */
public class KeptMemberFilter implements MemberVisitor {
    private final MemberVisitor memberVisitor;

    /**
     * Creates a new KeptMemberFilter.
     * 
     * @param memberVisitor the member visitor to which the visiting will be delegated.
     */
    public KeptMemberFilter(MemberVisitor memberVisitor) {
        this.memberVisitor = memberVisitor;
    }

    // Implementations for MemberVisitor.

    public void visitProgramField(ProgramClass programClass, ProgramField programField) {
        if (KeepMarker.isKept(programField)) {
            memberVisitor.visitProgramField(programClass, programField);
        }
    }

    public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod) {
        if (KeepMarker.isKept(programMethod)) {
            memberVisitor.visitProgramMethod(programClass, programMethod);
        }
    }

    public void visitLibraryField(LibraryClass libraryClass, LibraryField libraryField) {
        if (KeepMarker.isKept(libraryField)) {
            memberVisitor.visitLibraryField(libraryClass, libraryField);
        }
    }

    public void visitLibraryMethod(LibraryClass libraryClass, LibraryMethod libraryMethod) {
        if (KeepMarker.isKept(libraryMethod)) {
            memberVisitor.visitLibraryMethod(libraryClass, libraryMethod);
        }
    }
}